I wonder if periodically lubricating those wear points with a high-temp lubricant would make a difference. Perhaps working in a little anti-seize grease,.. or maybe a few drops of of a graphite or moly- containing lube like Loctite every so often. Has anyone tried that? Loctite might be better since it would probably attract less dirt after the carrier evaporates, leaving the graphite. Maybe some other dry-film lubricant such as Dow 321 would be even better.